Visual Correspondence

Analysing Letters through Data Visualisation

What to do

About the Visualisations

About the Visualisations

What to do

From the top right panel select a collection or collections. To select multiple collections hold down CTRL while clicking if you are on a PC, or CMD while clicking on a Mac. The number beside each collection name indicates the number of letters in that collection.Example: Select 'All Collections' and click 'Submit Collections'

Build up your query by selecting from the People, Places, Dates or Years you are interested in. Again you can select multiple values. From a temporal perspective, choose either Dates or Years by clicking on the appropriate tab. Leave the parameters at their default settings to return everything for the selected collections.
Example: Under 'Or enter a name' enter Yeats

Select the type of graph you want to generate.
Example: From the Choose how you want to see the data dropdown select Force-directed Network

Click on Submit Parameters

Please note: Unless otherwise indicated, by default the numbers returned do not represent the number of individual letters. Instead they represent the number of times a correspondent is associated with each letter, i.e. as sender or recipient. For instance Roger Casement is associated with a letter 26 times, 25 times as sender and once as a recipient. However, it is possible to get the numbers of letters by restricting the query to senders or recipients only. You can do this by selecting "Senders", use the dropdown to select "Sent by these people", and then selecting the senders from the people list (use CTRL + a, or CMD + a for Mac, to select all).

Not all visualisations are suitable for all collections. Indeed some collections are too large (Early Modern Letters Online) or too varied (Yale University Library - General Collection Manuscript Miscellany) to work properly with all visualisations. This is often a limitation of the browser, though sometimes the data is simply not appropriate. (In an effort to minimise this problem, some of the larger collections have been broken up into sub-collections based on years.) In such cases it is better to work with a selection from the chosen collections or choose a different graph. In general maps will work with all collections, Bubble and Pie charts work better with selections. Each graph has interactive elements to change the view of the data (from people to places, for instance) or to allow you to zoom in (Treemaps and Circle Packing), so try out the possibilities of each visualisation.

Roll over a data visualisation title to get more information and to find out if it is suitable for your query.

Map

Facetted Map

Time Map

Time Map with slider

Network

Force-directed Network

Bar Chart

Pie Chart

Ring Chart

Scatter Plot

Line

Bubble

Lollipop

Grouped Area

Multiple Step Area

Circle Packing

Zoomable Circle Packing

Treemap

Indented Tree

Zoomable Sunburst

Dendrogram

Rotating Cluster Wheel

Hierarchical Edge Bundling

Timeline

Table

Map

This map displays origins (red) and destinations (blue) and the path between the two. As well as a zoom facility,
there are five other map types available, and origins, destinations, or paths can be toggled on or off using the controls
in the top right corner (click on the layers symbol to activate). It is good for almost any collection (depending on the availability of location data).

Facetted Map

In a manner similar to the standard map view, this map displays origins (orange) and destinations (blue). As well as a zoom facility and the ability to
grab and move the map, the results displayed can be narrowed using a combination of sender, recipient, origin, destination, and year (facets). It is good for
almost any collection (depending on the availability of location data).

Time Map

This visualisation tries to add a sense of time to the map view. Origins and destinations are represented by coloured discs. Going from red (the earliest)
to blue (the latest), the date a letter was sent is colour-coded. Also the larger the circle the older the date of the letter.

Time Map with Slider

This visualisation adds time to the map view through the use of a slider and animation. Drag the slider to see the results for a given year or animate the display
to visualise the flow of correspondence over time. This should work for all collections. Indeed it is capable of displaying all letters from all collections on 'Visual Correspondence' on one map.

This map builds on the mapping library, Leaflet, and the javascript framework, JQuery.

Network

This shows the network of correspondents using arrows to indicate the flow from sender to recipient. It will work with all collections, but the greater the amount of data, the
more difficult it is to see the correspondents. Useful for small collections

Force-directed Network

This shows the network of correspondents for a given selection, using colour-coding to show different collections. The larger the node the more correspondence
for that person. Click on a node to highlight all the people who interacted with that person. Double-click on the window to zoom in or hold down your mouse button
to drag the graph around. This graph dynamically alters itself to cluster those with more interaction with each other. It takes a few seconds to settle.
While this should work for almost all collections the more data the slower this settling. It will stop automatically and may stop too soon to be useful.
It works best with smaller datasets.

Bar Chart

A standard of data visualisation, this maps one facet of the data - person, location, year, number of occurrences - against another. It is most effective when mapping
number of occurrences on one axis against one of the others, e.g. year. Hover over a bar to get the full number count. Depending on the facets chosen, it works with all the contents of each collection except Early Modern Letters Online and the Mark Twain Letters.
In the case of larger collections, it is recommended to use selections based on people, places or dates.

This map builds on the graphics library, Dimple, which in turn builds on D3.

Pie Chart

Another stalwart of data visualisation, this charts one facet of the data - person, location, year - which you can control via the options underneath the graph. Hover over
a segment to get the full detail. Depending on the facets chosen, it works with all the
contents of each collection, though depending on the amount of data it may take a while to load. In the case of these use selections.

This map builds on the graphics library, Dimple, which in turn builds on D3.

Ring Chart

A slight variant of the pie chart, this charts one facet of the data - person, location, year - which you can control via the options underneath the graph. Hover over
a segment to get the full detail. Depending on the facets chosen, it works with all the
contents of each collection, though depending on the amount of data it may take a while to load. In the case of these use selections.

This map builds on the graphics library, Dimple, which in turn builds on D3.

Scatter Plot

The scatter plot graph will indicate the dispersal of one vector against another. The colour of the dots links all data to a third vector, e.g. the correspondent. Hovering over a dot will provide some more detail.

Line

Line Graphs are used to to display the development of quantitative values over an interval or time period and are good for showing trends.
Building on the Scatter Plot, this Line Graph also links all associated data based on a third vector but with more clarity.
For instance, while showing the number of letters sent over, it will also indicate, via the line and colour of that line, who sent/received the letters. Hovering over a dot will provide some more detail.

Bubble

Building on the Line Graph, the Bubble Graph also links all associated data based on a third vector. For instance, while showing the number of letters sent each year, it will also indicate, via the line and colour of that line, who sent the letters. The Bubble Graph also gives an idea of the relative quantity of letters at each point through the sizing of the bubbles. Hovering over a bubble will provide some more detail.

Lollipop

Similar to the Scatter Plot, the Lollipop Graph shows graphs two series of data against one another, while also visualising a third vector through the use of miniature pie charts. For instance, while showing the number of letters sent each year, it will also indicate, via the 'lollipops', the relative amounts sent/received by each correspondent. Hovering over each segment of a lollipop will provide some more detail.

Multiple Step Area

Circle Packing

All related places or recipients are colour coded together depending on their parent country or sender. The sizing of the circles indicates the relative distribution of correspondence.

Zoomable Circle Packing

Places are grouped by country, and letters received are grouped by sender. Clicking on a circle will expand it to make its constituent places or recipients visible. The sizing of the circles indicates the relative distribution of correspondence.

Treemap

Using area to show the number of letters associated with either a place or person, all places in a
particular country, or all recipients of letters from a particular sender are coded with the same colour. Click on
a colour to zoom in on its detail. Click again to zoom out. If
a name does not appear on a rectangle due to space, hover over it for more detail. Though it might take some time
to load this will work for all letters in all collections.

Indented Treemap

By default the tree will be closed. Click on the blue rectangles to see where they branch to, starting with the first entry.
This will show locations or people (select using the control in the top right corner). It is particularly
useful for getting detail on particular places or correspondents, showing the 'to' and 'fro' of each with regard to the letters to which they are associated. Though
it might take some time to load this will work for all letters in all collections.

Zoomable Sunburst

Clicking on a segment will expand it, while clicking the central circle will move back a stage. Segments are colour coded by country or sender. The relative sizing of each segment indicates the relative quantity of correspondence associated with that segment. This will work with any collection, but large datasets can be difficult to read.

Dendrogram

While not good for large collections (it is difficult to read the labels), this is useful for seeing the flow of correspondence from one correspondent to another. Click on the shaded circles to expand them.

Rotating Cluster Wheel

While not good for large collections (it is difficult to read the labels), this is useful for seeing the flow of correspondence from one correspondent to another and is an alternative to the Dendrogram. Click down on the graph and move your mouse to spin the graph to a more readable position.

Hierarchical Edge Bundling

Rolling over each label will highlight its connections. Changing the tension will aid in reading the data. Places or people can be examined. Unfortunately large amounts of data can be difficult to read.

Timeline

A sortable timeline. Search for a specific word or use the facet lists - Sender, Recipient, Origin, Destination,
and Year - to narrow your results. There are links to further information for each letter; just click on the title in the timeline.
This will work for all letters in all collections.

Table

A sortable, facetted table. Search for a specific word or use the facet lists - Sender, Recipient, Origin, Destination,
and Year - to narrow your results. Click on a column title to sort by the field. There are links to further information on each
letter as well as links to the original web page where available.
This will work for all letters in all collections.

Niall O'Leary Services accepts no liability in respect of the accuracy of data on this website.
All data on this site is presented as is and visitors use it at their own risk. Outside of metadata no letter content has been used on this website. All letters and detail on all people's letters are listed.